Modeling minimum and maximum detectable deformation gradients of interferometric SAR measurements

A new functional model for determining the minimum and maximum detectable deformation gradients of interferometric synthetic aperture radar (InSAR) is developed. The model incorporates both the interferometric coherence and the look number, representing an extension to the existing models that consider only the interferometric coherence. Experimental results with Envisat ASAR data show that the new model performs well for interferograms with different look numbers and interferometric coherences. The model can serve as an important tool in determining whether InSAR technology can be used effectively to monitor a particular ground deformation. In addition, the model can also be used to determine the optimum look number for multi-looking operations to result in the best deformation monitoring results.

► We develop a new model for determining the detectable minimum and maximum deformation gradient of InSAR.
► Unbiased coherence estimation is considered when model statistics.
► The constraints for a coherence value equal to one are modified.
► Coherence based models under the look number L = 1, 5 and 20 are presented.
► The model incorporates both coherence and the look number is developed.